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41.
T Ibrahim B Bloch CN Esler KR Abrams WM Harper 《Annals of the Royal College of Surgeons of England》2010,92(3):231-235
INTRODUCTION
The aim of this study was to evaluate temporal trends in the prevalence of primary total hip and knee replacements (THRs and TKRs) throughout the Trent region from 1991 to 2004.PATIENTS AND METHODS
The Trent Regional Arthroplasty Study records details of primary THR and TKR prospectively and data from the register were examined. Age and gender population data were provided by the Office for National Statistics.RESULTS
A total of 26,281 THRs and 23,606 TKRs were recorded during this period. Analysis showed that females had an increased incidence rate ratio (IRR) for both primary THR (IRR = 1.29; 95% CI 1.26–1.33; P < 0.001) and TKR (IRR = 1.17; 95% CI 1.14–1.20; P < 0.001). Patients aged 74–85 years had the largest IRR for both primary THR (IRR = 6.7; 95% CI 6.4–7.0; P < 0.001) and TKR (IRR = 15.3; 95% CI 14.4–16.3; P < 0.001).CONCLUSIONS
The prevalence of primary TKR increased significantly over time whereas THR remained steady in the Trent region between 1991 and 2004. 相似文献42.
Glycoproteins present in human follicular fluid that inhibit the zona- binding capacity of spermatozoa 总被引:1,自引:0,他引:1
Previous studies have suggested that human follicular fluid contains
factors that reduce the zona-binding capacity of spermatozoa. The present
study provides further evidence of the existence of such factors. Using the
hemizona binding assay (HZA), we have shown that the inhibitory effect of
human follicular fluid on the zona-binding capacity of spermatozoa is
concentration-dependent, an inhibitory effect being detected when the
concentration of human follicular fluid was > or = 10%. A 1%
concentration of human follicular fluid did not possess this inhibitory
activity. Heating human follicular fluid at 56 degrees C for 30 min did not
affect its inhibitory properties; treatment with proteinase-K abolished
such inhibition. Human follicular fluid was fractionated sequentially by
concanavalin-A affinity chromatography, Mono Q ion-exchange chromatography
and Superose-12 gel filtration. The zona binding inhibitory activity
resided in the fraction which bound to the lectin and Mono Q column and
contained molecules with native molecular weights of 32 and 192 kDa. Sodium
dodecyl sulphate-polyacrylamide gel electrophoresis analysis suggested that
the 192 kDa glycoprotein was a tetramer, while the 32 kDa glycoprotein
remained as a single molecular species under denaturing conditions. We
conclude that two glycoproteins were responsible for the zona binding
inhibitory activity of human follicular fluid. The physiological role of
these factors remains unclear.
相似文献
43.
Multiple sclerosis: II. Effects of prothymosin alpha on the autologous and allogeneic MLR in patients with multiple sclerosis. 总被引:1,自引:0,他引:1 下载免费PDF全文
G J Reclos C N Baxevanis C Sfagos C Papageorgiou G C Tsokos M Papamichail 《Clinical and experimental immunology》1987,70(2):336-344
We have recently demonstrated that peripheral blood monocytes from patients with multiple sclerosis (MS) have a defect in stimulating autologous and allogeneic T lymphocytes. This defect was found to correlate with disease activity. In this report we demonstrate that prothymosin alpha (ProT alpha), a rat thymus fraction 5 polypeptide, restores the MS monocyte stimulatory defect. The concentrations of ProT alpha which induced optimal enhancement of the mixed lymphocyte responses (MLR) were significantly higher when monocytes from patients with active disease were used as stimulators than when monocytes from patients with inactive disease were used. T4+ cells tested with autologous stimulatory monocytes harvested from an inactive stage of MS exhibited considerably higher proliferative responses than when stimulated with autologous monocytes obtained from an acute relapse. The decreased autologous proliferation of T4+ cells in MS patients was restored to normal levels after preincubation with ProT alpha in the environment of autologous monocytes. Our results demonstrate that ProT alpha is capable of fully restoring the deficient stimulatory function of MS monocytes and monocyte-associated functional defects of MS-derived T4+ cells. 相似文献
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47.
The Sox10(Dom) mouse: modeling the genetic variation of Waardenburg-Shah (WS4) syndrome 总被引:10,自引:0,他引:10 下载免费PDF全文
Southard-Smith EM Angrist M Ellison JS Agarwala R Baxevanis AD Chakravarti A Pavan WJ 《Genome research》1999,9(3):215-225
Hirschsprung disease (HSCR) is a multigenic neurocristopathy clinically recognized by aganglionosis of the distal gastrointestinal tract. Patients presenting with aganglionosis in association with hypopigmentation are classified as Waardenburg syndrome type 4 (Waardenburg-Shah, WS4). Variability in the disease phenotype of WS4 patients with equivalent mutations suggests the influence of genetic modifier loci in this disorder. Sox10(Dom)/+ mice exhibit variability of aganglionosis and hypopigmentation influenced by genetic background similar to that observed in WS4 patients. We have constructed Sox10(Dom)/+ congenic lines to segregate loci that modify the neural crest defects in these mice. Consistent with previous studies, increased lethality of Sox10(Dom)/+ animals resulted from a C57BL/6J locus(i). However, we also observed an increase in hypopigmentation in conjunction with a C3HeB/FeJLe-a/a locus(i). Linkage analysis localized a hypopigmentation modifier of the Dom phenotype to mouse chromosome 10 in close proximity to a previously reported modifier of hypopigmentation for the endothelin receptor B mouse model of WS4. To evaluate further the role of SOX10 in development and disease, we have performed comparative genomic analyses. An essential role for this gene in neural crest development is supported by zoo blot hybridizations that reveal extensive conservation throughout vertebrate evolution and by similar Northern blot expression profiles between mouse and man. Comparative sequence analysis of the mouse and human SOX10 gene have defined the exon-intron boundaries of SOX10 and facilitated mutation analysis leading to the identification of two new SOX10 mutations in individuals with WS4. Structural analysis of the HMG DNA-binding domain was performed to evaluate the effect of human mutations in this region. 相似文献
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Factor IXTaipei9 is a factor IX variant from a hemophilia B patient with reduced levels of circulating protein molecules (cross-reacting material reduced, CRM). This variant contained a glycine (Gly) to glutamic acid (Glu) substitution at the 207th codon of mature factor IX. The functional consequences of the Gly-->Glu mutation in factor IXTaipei9 (IXG207E) were characterized in this study. Plasma-derived IXG207E exhibited a mobility similar to that of normal factor IX on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Its specific activity was estimated to be 3.5% that of the purified normal factor IX in a one-stage partial thromboplastin time assay (aPTT). Cleavage of factor IXG207E by factor XIa or factor VIIa-tissue factor complex appeared to be normal. When the calcium-dependent conformational change was examined by monitoring quenching of intrinsic fluorescence, both normal factor IX and IXG207E exhibited equivalent intrinsic fluorescence quenching. Activated factor IXG207E (IXaG207E) also binds antithrombin III equally as well as normal factor IXa. However, aberrant binding of the active site probe p-aminobenzamidine was observed for factor XIa-activated factor IXG207E, indicating that the active site pocket of the heavy chain of factor IXaG207E was abnormal. Moreover, the rate of activation of factor X by factor IXaG207E, as measured in a purified system using chromogenic substrates, was estimated to be 1/40 of that of normal factor IXa. A computer-modeled heavy-chain structure of factor IXa predicts a hydrophobic environment surrounding Gly-207 and this Gly forms a hydrogen bound to the active site serine-365. The molecular mechanism of the Gly-->Glu mutation in factor IXTaipei9 might result in the alteration of the microenvironment of the active site pocket which renders the active site serine-365 inaccessible to its substrate. 相似文献